MMQA20VT3 Transient Voltage Suppressor (TVS) Diode - Equivalent & Substitute Parts

Part Overview

The MMQA20VT3 is a unidirectional Zener-type transient voltage suppressor manufactured by onsemi, designed for general-purpose overvoltage protection in surface-mount applications. This component features a 15V reverse standoff voltage with 28.6V maximum clamping voltage and 840mA peak pulse current capability in an SC-74 package. The part is currently classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing design support and procurement continuity.

Substiute Parts

MMQA20VT3

onsemiIn Stock: 6817MMQA20VT3 Datasheet

Current PartRFQ

MMQA20VT1G

onsemiIn Stock: 7289MMQA20VT1G Datasheet

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BZA420A,115

Nexperia USA Inc.In Stock: 12207BZA420A,115 Datasheet

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BZA420A,125

Nexperia USA Inc.In Stock: 7007BZA420A,125 Datasheet

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BZA420A,135

Nexperia USA Inc.In Stock: 813BZA420A,135 Datasheet

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BZA420A,165

Nexperia USA Inc.In Stock: 1236BZA420A,165 Datasheet

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BZA456A,115

Nexperia USA Inc.In Stock: 15343BZA456A,115 Datasheet

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BZA456A,125

Nexperia USA Inc.In Stock: 836BZA456A,125 Datasheet

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BZA456A,135

Nexperia USA Inc.In Stock: 11108BZA456A,135 Datasheet

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BZA456A,165

Nexperia USA Inc.In Stock: 11152BZA456A,165 Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution of the MMQA20VT3 is determined by the following critical electrical and mechanical parameters:

Primary Substitution Criteria:

• Voltage - Reverse Standoff: 15V nominal operation
• Voltage - Clamping (Max) @ Ipp: 28.6V maximum protection threshold
• Current - Peak Pulse (8/20µs): 840mA minimum capability
• Unidirectional Channels: 4-channel configuration
• Mounting Type: Surface Mount
• Package Compatibility: SC-74 or equivalent footprint

Substitute Categories Identified:

1. Direct onsemi Equivalent (MMQA Series): MMQA20VT1G maintains identical electrical specifications with active product status and improved RoHS3 compliance. Packaging differs only in tape & reel format.

2. Nexperia BZA420A Series (20V Standoff): BZA420A,115 / BZA420A,125 / BZA420A,135 / BZA420A,165 provide 20V reverse standoff with 28V clamping voltage. These parts meet automotive-grade AEC-Q100 qualification and RoHS3 compliance. Package designation is 6-TSOP with equivalent SC-74 footprint compatibility.

3. Nexperia BZA456A Series (5.6V Standoff): BZA456A,115 / BZA456A,125 / BZA456A,135 / BZA456A,165 operate at lower voltage ratings (5.6V standoff, 8V clamping) with higher peak pulse current (3A). These are suitable only for applications requiring lower voltage protection thresholds.

Parameter Comparison

Engineering Selection Recommendations

Tier 1 - Recommended Direct Replacement:

MMQA20VT1G is the primary substitute for MMQA20VT3. This part maintains identical electrical specifications (15V standoff, 28.6V clamping, 840mA peak pulse current) and 4-channel configuration. The part is in active production status with RoHS3 compliance, addressing the obsolescence and regulatory compliance limitations of the original component. Packaging format is tape & reel, suitable for automated assembly processes.

Tier 2 - Voltage-Compatible Alternative:

BZA420A series (BZA420A,115 / BZA420A,125 / BZA420A,135 / BZA420A,165) from Nexperia provides 20V reverse standoff with 28V clamping voltage, representing a 5V higher standoff rating. These parts carry automotive-grade AEC-Q100 qualification and RoHS3 compliance. The 6-TSOP package maintains SC-74 footprint compatibility. Selection among the four variants (115, 125, 135, 165) is determined by temperature grade and packaging reel specifications. Peak pulse current specifications are not provided for this series.

Tier 3 - Lower Voltage Applications Only:

BZA456A series (BZA456A,115 / BZA456A,125 / BZA456A,135 / BZA456A,165) operates at 5.6V reverse standoff with 8V clamping voltage. These parts are suitable only for applications requiring lower voltage protection thresholds and are not direct electrical equivalents for 15V standoff applications. Higher peak pulse current capability (3A) may benefit specific low-voltage protection circuits.

Frequently Asked Questions (FAQ)

Q: Can MMQA20VT1G be used as a direct replacement for MMQA20VT3?

A: Yes. MMQA20VT1G provides identical electrical performance with 15V reverse standoff, 28.6V clamping voltage, and 840mA peak pulse current. The primary difference is product status (active vs. obsolete) and RoHS3 compliance. Packaging format is tape & reel rather than bulk, which is standard for active production components.

Q: What is the difference between the BZA420A variants (115, 125, 135, 165)?

A: The numeric suffixes indicate different temperature grades and packaging reel specifications. All variants maintain identical electrical characteristics: 20V reverse standoff and 28V clamping voltage. Selection depends on your specific temperature operating requirements and assembly line reel compatibility.

Q: Can BZA420A series replace MMQA20VT3 in all applications?

A: BZA420A series has a 5V higher reverse standoff voltage (20V vs. 15V). This is acceptable for applications where the protected circuit operates below 15V nominal, as the higher standoff voltage provides equivalent protection margin. Verify that your circuit voltage does not exceed 15V nominal operation before substitution.

Q: Why are BZA456A parts listed if they have different voltage ratings?

A: BZA456A series (5.6V standoff, 8V clamping) operates in a different voltage protection class. These parts are not suitable for circuits requiring 15V standoff protection and are included only for reference in applications requiring lower voltage transient suppression.

Q: What is the significance of the 6-TSOP package designation for BZA420A and BZA456A parts?

A: The 6-TSOP package maintains SC-74 footprint compatibility, allowing direct PCB layout reuse. Both package designations reference the same physical form factor suitable for surface-mount assembly.

Q: Are all substitute parts RoHS3 compliant?

A: MMQA20VT1G and all BZA420A and BZA456A variants are RoHS3 compliant. The original MMQA20VT3 is RoHS non-compliant. Substitution with any recommended alternative addresses regulatory compliance requirements.

Q: What is the inventory status for these substitute parts?

A: MMQA20VT1G has 7,270 units in stock. BZA420A variants range from 731 to 12,150 units depending on the specific suffix. BZA456A variants range from 797 to 15,300 units. Inventory levels support production requirements for both low and high-volume applications.